REMOTELY CONTROLLED DEVICE FOR ROTATING THE STEERING WHEEL OF A MOTOR VEHICLE

Abstract: A remotely controlled device for rotating the steering-wheel of a vehicle consists of an upper portion for gripping the steering-wheel ring by means of jaws (1), of a central frame (14) carrying a motor (16) with the relevant motion transmission chain (10, 11, 12, 13, 15) and means for detecting and memorizing the rotations (17, 19, 22, 23, 24), and of a lower portion with supporting members (27, 28, 29, 30, 31) which provide the device with the base required to react to the steering-wheel reaction torque.

Description: "REMOTELY CONTROLLED DEVICE FOR ROTATING THE STEERING- WHEEL OF A MOTOR VEHICLE The present invention concerns devices for analysing and tuning motor vehicles, and in particular a remotely controlled device for rotating the steering-wheel and then taking it back to the starting position. It is known that the front steering wheels of motor vehicles require a periodical check and truing operation of their toe-in in order to verify the correctness of the various angles characterizing the forecarriage kinematic mechanism. In carrying out said toe-in operation, the front wheels are repeatedly steered one way and the other by means of the steering-wheel, in order to allow also the alignment of the steering-wheel spiders with the wheels, so that the driver is not obliged to keep the steering-wheel lightly rotated on one side to go straight. This rotation of the steering-wheel is presently carried out manually by the person carrying out the toe-in operation, which blocks the steering- wheel in the desired position by means of a suitable device, or by an assistant thereof which rotates and blocks the steering-wheel according to the instructions of the operator which is under the vehicle. The serious drawback implicit in this method is apparent, since in the first case the operator must continuosly get on and get off the vehicle with the problems implied therein: waste of time to get out of the pit or from under the lift, impossibility of visually verifying the wheel motion while it is being carried out, risk of smearing the vehicle interiors with his dirty hands or necessity of cleaning his hands every time he rotates the steering-wheel. In the second case, all these problems are avoided but at the cost of employing double labour, with all the problems of cost implied therein. The object of the present invention is to provide a remotely controlled device suitable to replace the operator's assistant, so that the operator himself carries out the required steering-wheel adjustments with no need to move from his working position. A further object of the captioned device is taking back the steering- wheel exactly to the starting position at the end of the operation. These objects are achieved by means of a device having the characteristics cited in claim 1. Therefore, the device according to the present invention allows the advantageous replacement of the additional labour required in conventional toe-in operations, i.e. it allows a single operator to carry out the operation with significant time and labour savings. Another advantage of the captioned device is its capacity of memorizing the steering-wheel starting position and the following rotations thereof, so that it is capable of automatically taking back the steering-wheel to said position at the end of the operation. A further advantage stems from the possibility of carrying out a very fine and precise adjustment of the steering-wheel movement, absolutely impossible to be achieved manually, so that the truing of the wheel toe-in can be carried out with great precision. These and other advantages and characteristics of the device according to the present invention will be apparent from the following detailed description of a preferred embodiment thereof, reported as a non- limiting example, referring to the annexed drawings wherein: Fig.1 is a partly see-through view of the captioned device, wherein the movement of the lower portion is indicated by the dotted lines; Fig.2 is a see-through view of the upper portion of the device mounted on a steering-wheel; and Fig.3 is a front view of the device mounted on a steering-wheel and with the lower portion in the retracted position. Referring to fig.1, there is seen that the captioned device is made up by an upper portion for gripping the steering-wheel, a central frame carrying the driving and memory apparatus and a lower supporting portion. Referring to fig.2, there is shown that the ring I of the steering-wheel is gripped by means of jaws 1 substantially hook-shaped and internally provided with a coating 2 suitable to avoid that said jaws 1 slip on said ring 1 and/or scratch it. In the described embodiment, there are four jaws 1 (fig.3) made of flexible steel, however they could be different in number, position and material, as far as they continue to carry out their gripping function on the steering-wheel. Jaws 1 slide on an arm 3 wherein two longitudinal guides 4 are formed, and the opening and closing motion of said jaws 1 is controlled by a knob 5 which is coaxially integral with a gear 6 which engages two rack members 7, each of which carries at one end thereof the respective jaws 1. To maintain the pressure of the latter on the ring I of the steering- wheel, each of the members 7 is connected, at the end opposite to that of jaws 1 , to an end of arm 3 through a spring 8 which exerts a traction such as to keep jaws 1 tightly gripping, and whose force must be overcome by means of knob 5 in order to remove the device from the steering-wheel. Turning back to fig.1 , there is seen that arm 3 is connected to the rest of the device through a plate 9 which is driven into rotation by a shaft 10 integral thereto which takes the motion from a gear 11 keyed thereon and driven in turn by gears 12 for reducing and transmitting the motion coming from a driving gear 13. This series of gears is mounted within a central frame 14, outside which, on the lower portion thereof, a reducer 15 which operates gear 13, an electric motor 16 and a processor 17 controlling the operation of the device are mounted. For safety purposes, reducer 15 includes an adjustable clutch 18 which disengages motor 16 in case the device meets with an excessive resistance against the rotation of the steering-wheel, so as to prevent possible damages to the device itself and/or to the steering kinematic chain. The present device further includes the means for the remote control which, in the illustrated embodiment, consist of a radio receiver (not shown) picking up the pulses of a radio control, but they might as well consist, in particular cases of interferences, of a wire control. On the upper portion of frame 14, on the outside thereof, there is mounted a knob 19 coaxial with shaft 10 and provided with an internal clutch 20 suitable to disengage said knob 19 from said shaft 10; between the end of shaft 10 and knob 19 there is interposed a disc 21 , integral with the latter, provided with a tongue 22 which, upon rotation of said disc 21 , passes between two photocells 23 positioned below shaft 10 and connected to processor 17 which thus detects the passage of tongue 22, said passage being also indicated by the switching on of an indicator light 24 located in front of said photocells 23. Referring now also to fig.3, there is seen that frame 14 is connected at the bottom to the device portion which provides the support to react to the steering-wheel rotation torque. A central structure 25, centered with respect to frame 14, contains a battery, for operating motor 16, which is charged through proper electrodes 26 outside the battery container; the ends of two rods are pivoted on each side of structure 25, a main rod 27 in a more advanced position and a secondary rod 28 in a more receded position towards the steering-wheel, both of them being pivoted at the other end on a support rod 29 which is provided at the bottom with a support plane 30, also pivoted on said rod 29 and provided with a pair of feet 31. For the manual operation of the supporting members, the main rod 27 extends forward into a lever 32 integral therewith, and it is provided with an external spring 33 suitable to retain the supporting structure in the bent position upwards and subsequently, once in the downwards rotation indicated by arrow A the return point has been surpassed, to exert a pressure on the support rod 29 to achieve the self-adjustment of the support plane 30. The operation of the device according to the present invention is now illustrated, in particular with reference to the starting position memorization function. As already mentioned in the description of the device, the installation on ring I of the steering-wheel is carried out through jaws 1 which are opened and then closed by means of knob 5, the steering-wheel being in any position; once jaws 1 have been properly tightened, the lower support structure is lowered, with the aid of springs 33, by pushing on levers 32 so that feet 31 lean on a reaction plane which, for example, is the seat bottom or the vehicle floor, and whose inclination with respect to the device is compensated by the self-orientation of the supporting planes 30 which are pivoted on rods 29. In case of leaning on a sinking surface such as the seat bottom, the presence of springs 33 allows to lower feet 31 until the plane reacts with a force equal to that of spring 33, thus avoiding sensible settling in the first phases of the steering-wheel rotation. Having thus provided the device with the base required to react to the steering-wheel reaction torque, the operator carries out the centering of the steering-wheel by operating motor 16, through the remote control, which puts into rotation arm 3 as indicated by arrow B, until he visually finds the alignment of spiders II of the steering-wheel. Once the steering- wheel is exactly centered on the vertical, the operator disengages knob 19 from shaft 10 by means of clutch 20 and rotates said knob 19, carrying along disc 21 , until he detects, by means of indicator 24, the alignment of tongue 22 with photocells 23; then he engages again knob 19 on shaft 10 and resets the rotation count carried out by processor 17, which, from now on, provides the memorization of the direction and number of the passages of tongue 22 through photocells 23. After having carried out the setting operation of the present device, the operator can go below the vehicle to proceed to the forecarriage truing operation, with no further need to climb up to rotate the steering- wheel since the remote control allows him to carry out the steering of the wheels in the direction and for the angle required, with the possibility, for example by means of two different push-buttons, of a fine or rough adjustment of the steering angle. At the end of the truing, the operator sends the steering-wheel re¬ alignment command to processor 17, which said processor 17 carries out by taking into account the steering-wheel position as it results from the rotations it has memorized; in order to divide equally between the two directions of rotation the unavoidable mechanical plays present in the kinematic chain, the device does not immediately stop the steering-wheel at the starting position, but surpasses it and then comes back surpassing it in the opposite direction and so on, with an oscillation of decreasing amplitude around said starting position. Therefore, it is apparent that the device according to the present invention fully achieves the intended object of replacing the additional labour presently required, with the further advantage of a precision of rotation and of return to the starting position impossible to be manually achieved. All the members of the above-described embodiment may of course be replaced by equivalents thereof, for example a different system for detecting and memorizing the rotations, a different motion transmission chain, a different kind of motor, and so on.

Claims: CLAIMS 1. A remotely controlled device for rotating the steering-wheel of a motor vehicle and then taking it back to the starting position, characterized in that it consists of an upper portion for gripping the steering-wheel integrally mounted at the output of a transmission chain of the rotation motion transmitted by a motor, said transmission chain being connected through a central frame to a lower self-adjusting support portion suitable to provide the base required to react to the steering-wheel reaction torque, of means for detecting and memorizing the rotations, and of means for the remote control. 2. A device according to claim 1 , characterized in that the upper portion for gripping the steering-wheel includes a plurality of jaws (1 ) substantially hook-shaped suitable to grip the ring (I) of the steering- wheel and internally provided with a coating (2) suitable to prevent said jaws (1 ) from slipping on said ring (I) of the steering-wheel and/or from scratching it. 3. A device according to claim 2, characterized in that jaws (1) are slidably mounted on an arm (3) wherein two guides (4) are longitudinally formed, the closing and opening movement of said jaws (1 ) being controlled by a knob (5) to which a gear (6) engaging two rack members (7) is coaxially integral, jaws (1 ) being mounted on one end of the latter, each of said members (7) being connected, at the end opposite to that of jaws (1 ), to an end of said arm (3) through a spring (8) exerting a traction such as to keep jaws (1 ) tightly closed. 4. A device according to claim 1 , characterized in that the rotation motion is provided by an electric motor (16) and transmitted through a motion transmission chain consisting of a shaft (10) taking the motion from a gear (11 ) keyed thereon and operated in turn by gears (12) for reducing and transmitting the motion coming from a driving gear (13) connected to a reducer (15) located at the output of said motor (16), said gear series (11 , 12, 13) being mounted within a central frame (14). 5. A device according to claim 4, characterized in that reducer (15) also includes an adjustable clutch (18) suitable to disengage motor (16) in case of excessive resistance against the rotation of the steering-wheel. 6. A device according to claim 4, characterized in that it includes a receiver suitable to pick up the pulses sent out by a radio control for controlling motor (16). 7. A device according to claim 4, characterized in that it includes a port for inserting a wire control for motor (16). 8. A device according to claim 4, characterized in that the lower supporting portion includes a container (25) for the supply battery of motor (16) and a holder outside said container (25) for electrodes (26) for charging said battery. 9. A device according to claim 4, characterized in that the means for detecting and memorizing the rotations include a knob (19) coaxial with shaft (10) and provided with an internal clutch (20) suitable to disengage said knob (19) from said shaft (10), a disc (21), interposed between the end of shaft (10) and knob (19) and integral with the latter, provided with a tongue (22) which passes between two photocells (23) upon rotation of said disc (21 ), a processor (17) connected to said photocells (23), and an indicator light (24) which shows the passage of said tongue (22) between photocells (23). 10. A device according to claim 1 , characterized in that the lower supporting part includes a central structure (25) on both sides of which the ends of two rods are pivoted, a main rod (27) in a more advanced position and a secondary rod (28) in a more receded position towards the steering-wheel, both of them being pivoted at the other end on a support rod (29) which is provided at the bottom with a support plane (30), also pivoted on said rod (29) and provided with a pair of feet (31 ), said rod (27) being further provided with a forward lever (32) integral therewith and an external spring (33) suitable to retain the supporting members in the bent position and to exert a pressure on rod (29) when the supporting mechanism is extended.

Inventors: CORDIOLI SERGIO, CORDIOLI, SERGIO
Applicants: CORDIOLI SERGIO, CORDIOLI, SERGIO
Application year: 1994
Main classification: B60S5
IPC codes: B60S5, B62D1, G01M17